xiv INTRODUCTION 



of one individual. Thus we have the rather short stout limbs of equal 

 length in Pithecus, the lengthened slender limbs of Ateleus, the long 

 arms and short legs of Hylobates and Symphalangus, and carried 

 to an extreme, considering the difference in size, in Pongo, where arms 

 and hands reach nearly to the ankles when the animal is in an erect 

 position. All kinds of texture characterize the pelage of the Primates, 

 from velvety softness to one that is coarse and harsh. The hair 

 assumes various arrangements, sometimes forming coronal or occipital 

 crests, occasionally both, or fringing the face with obtrusive whiskers, 

 or projecting over the forehead like the peak of a cap. Long curled 

 moustaches are rarely present, as in a species of Leontocebus, 

 exhibiting a remarkable growth. In many species the hair of the head 

 is short and compact, sometimes with horn-like erections over the 

 forehead, or on the sides of the head as in Cebus, while in one species 

 Pithecus albibarbatus, the entire face is surrounded and the head 

 covered by long hair in the semblance of a huge wig. On the body the 

 hair is often long over the shoulders forming a mantle, and in other 

 cases falls from the sides or over the rump in long graceful fringes 

 as in most of the black species of Colobus. The tail as a rule 

 is covered by short hair, but the end is sometimes tufted as in Rhino- 

 piTHECUS and Colobus, and these tufts or tassels in some species of 

 the last genus are greatly enlarged, equal in one species to one third 

 the length of the tail. Only one species has a bare tail with end tufted 

 Simias concolor, an extraordinary animal. All colors are shown in 

 the different pelages many of vivid and contrasting hues, and while 

 some one member of nearly all the genera has bright coloring, probably 

 Lasiopvga, embracing as it does such a large number of species, con- 

 tains more highly colored members than any other genus of the Pri- 

 mates. 



Beards are not infrequently met with, in fact in Alouatta this 

 appendage to the face of the species is rather characteristic of the 

 genus ; and in all the Families, save Pongiid.e, the hairs of the arms 

 are directed towards the wrist, but in the members of that Family the 

 hairs of arm and forearm grow in opposite directions the first down- 

 ward and the latter upward meeting at the elbow, and as it is supposed 

 these great Apes usually sit with their arms crossed, Darwin imagined 

 that this peculiar arrangement of the hair was to permit the rain to 

 run off at the elbow. Ears of the Primates are well developed and 

 pointed, but the lobe is absent, the Gorilla alone having it present in 

 a rudimentary condition. The voice of the Apes is described in the 

 Gorilla as a roar, but in the Chimpanzee as a gruff bark-like tone. 



